DROUGHT RESPONSE PLAN

Mission: To provide safe, sustainable and reliable water and wastewater utility services to our customers with superior quality and value.

Vision: To set the standard of excellence for community-based water and wastewater utility services through innovative practices in finance, operations and resource management.

The goal of a coordinated Drought Response Plan is to maintain the health, safety and economic vitality of the community to the extent possible. This Drought Response Plan (Plan) is designed to maximize available water supplies and reduce water use during times of water shortage caused by drought.

Providing a reliable supply of water, which is the central mission of Centennial Water and Sanitation District (Centennial Water), requires being prepared for droughts of varying degrees and duration. Proper planning before a water shortage occurs from drought, allows for the selection of appropriate drought responses consistent with the varying severity of droughts.

This Plan outlines guidelines Centennial Water will use to manage water supply and water use during a period of drought. These guidelines are designed to maintain the health, safety and economic vitality of the community; to avoid adverse impacts to public activity and quality of life for the community; and to consider the needs of differing customer categories as much as possible. The Plan also outlines communication strategies Centennial Water may implement during a period of drought.

Because each water shortage event from drought is different, developing a set of hard-and-fast rules to apply to all drought situations is not practical. Rather, these guidelines are intended to provide a framework for timely drought response while maintaining flexibility to respond to unique water-shortage conditions. The guidelines define objectives and tactics for drought responses Centennial Water staff may recommend to the Centennial Water Board of Directors (the Board) for implementation. The Board may adjust or refine its response as it deems appropriate.

This Plan is a product of lessons learned from past drought conditions in Centennial Water’s service area and the Denver metropolitan area and will be updated as needed. The Plan is in accordance with Centennial Water’s Rules and Regulations (Article V, Water Conservation; Article VII, Violations, Penalties, and Complaints; and, Article VIII, Fees and Charges) and the Highlands Ranch Metro District Rules and Regulations (Article VI, Water Conservation; Article VIII, Violations Penalties and Complaints; and, Article IX, Fees and Charges).

Centennial Water recognizes the need to develop a drought response plan that provides a menu of options that can be implemented to ensure Centennial Water can provide sufficient water for essential purposes in its service area. This Plan is also intended to be a guide for the Board to facilitate decision-making.

Drought response plan implementation is a dynamic process that evolves as conditions change and new information becomes available. This Plan includes specific mandatory measures and communication strategies that may need to be implemented when certain water-shortage conditions occur due to drought. All drought response actions taken by Centennial Water are subject to approval by the Board.

1.1 Drought Response Plan Components

The Plan consists of:

 Drought Severity Indicators – A variety of factors that should be considered in choosing an appropriate water-shortage response.

 Drought Response Tools – A description of the most common tools Centennial Water may use during a water shortage.

 Drought Response Actions – Guidelines for augmenting water supplies and reducing water use during times of drought conditions.

1.2 Defining Drought

A drought, in the most general sense, is a deficiency of precipitation over an extended period, resulting in a water shortage for some beneficial activity or environmental purpose. A water shortage from drought occurs when available water supply from anticipated runoff and storage is reduced to a level that supporting customer demands is at risk. Not knowing exactly when a drought begins, when it will end, and its severity makes uncertainty one of the defining characteristics of drought.

Drought is a normal, recurring feature of the climate in most parts of the world. Water shortages from drought can occur quickly and require immediate response or may occur gradually, with multiple months or years passing before any response is required. A variety of factors are at play in determining how long a drought response will be required.

1.3 Supply

Colorado’s climate is generally characterized as semi-arid and, in the South Platte River basin, much of the water supply in the non-mountainous areas is dependent on the seasonal snowpack accumulation in the mountains that is then delivered to the various tributaries, diversion ditches, and storage reservoirs. Nontributary groundwater stored in the Denver Basin aquifers beneath Centennial Water’s service area is also a source of supply, but this water is nonrenewable.

Centennial Water’s water supply includes both surface water and nontributary groundwater, which in most years is more than sufficient to meet the annual demands of Centennial Water’s customers. The surface water supply is comprised of a combination of junior and senior water rights on the South Platte River, surface water leases, and storage rights. Centennial Water’s surface water is stored in four reservoirs with a combined storage volume of more than 17,412 AF. However, in a dry year the estimated yield of surface water is only about 9,200 AF.

The nontributary groundwater supply is stored in three Denver Basin bedrock aquifers beneath Highlands Ranch with an annual appropriation of about 18,000 AF. However, well pumping capacity limits the potential annual groundwater yield to approximately 8,000 AF to 9,000 AF, or from about 7.25 MGD to 8.0 MGD flow rate.

Shifts in weather patterns can be substantial from year-to-year and decade-to-decade, affecting both water supply and water use. Centennial Water constantly monitors reservoir levels and ensures they are managed effectively and efficiently.

1.4 Long-term Customer Water Efficiency Efforts

Centennial Water has always been committed to water efficiency and customer outreach. The water-use restrictions described in this Plan should not be confused with ongoing water efficiency efforts, described in Centennial Water’s Water Efficiency Plan that can be viewed on Centennial Water’s website. The Water Efficiency Plan is reviewed annually and updated at least every seven years. These efforts for all customers include the use of low water-use fixtures, creation of individual water budgets since 2003, an escalating rate structure and the following permanent lawn watering rules, which are summarized below (Highlands Ranch

Metro District Rules and Regulations, Exhibit A-2, Water Conservation Measures):

Water Use

 Wasteful use of water is prohibited at all times. Examples include:

• Excess water flowing in street gutters from irrigation or other outdoor uses.

• Unrepaired leaks or fixture malfunctions that lead to excess water use

Mandatory Outdoor Water Restrictions: The following restrictions apply at all times:

 Outdoor irrigation is prohibited between the hours of 10 a.m. and 6 p.m. from May 1 to September 30, with the exception of prior approved daytime watering permit

 Operation of an irrigation system for maintenance is allowed at any time. Maintenance is defined as actively observing an irrigation zone while it is operating to ensure it is functioning properly. A person must be visible at the location of the zone while it is running. Each zone must be turned off prior to leaving the location and not left running until the completion of a cycle.

 Hand watering of landscape materials is allowed at any time. Hand watering is defined as the application of irrigation from a hose held in the hand with a shut off valve; or a water-conserving method such as a drip, trickle, micro spray, deep root water device or watering can are used.

 Car washing is allowed at any time. However, if water for car washing is coming from a hose rather than a bucket, a hose end shut off device must be in use to prevent uninterrupted water flow.

Landscape Permit Outdoor Usage Adjustment:

 An additional allotment of irrigation for outdoor usage pursuant to the provisions of the Landscape Water Adjustment Request Form.

In addition to the above water conservation measures, Centennial Water highly recommends customers limit lawn watering with sprinklers to no more than three days per week.

There will be times when drought response actions are needed in addition to standard water efficiency efforts. Water-use restrictions are one example of a response action that is reserved for water shortage events caused by drought; but such restrictions are not intended for long-term application. Restrictions are used to minimize the impacts to community safety and quality of life and to assist in the return of normal water-supply and storage levels.

Water use restrictions will be lifted if the water-supply and storage levels return to normal or, in the case of a new normal for water availability, these restrictions, in part or whole, may become permanent as the Centennial Water service area adapts to new conditions.